The present invention provides a use for alkaline phosphatase for themanufacture of a medicament for the prevention or reduction of toxic LPSinflux through a mucosal lining of a mammalian body cavity. A source ofalkaline phosphatase is administered for the prophylaxis or treatment of LPSmediated or exacerbated diseases. The invention also provides compositionscomprising a source of alkaline phosphatase for the prevention or reduction of(toxic) LPS influx or passage through mucosal layers.